1. Technical Field of the Invention
The present invention relates to mobile telecommunications networks and, in particular, to the interworking of subscriber features and associated data for a roaming mobile station within multiple mobile telecommunications networks.
2. Description of Related Art
Within a typical mobile telecommunications network, each mobile subscriber has a subscription agreement with a mobile service provider. A centralized database, known as a home location register (HLR), stores subscription data associated with each subscriber. As a mobile station associated with a particular subscriber moves within a serving mobile telecommunications network, a telecommunications node, such as a mobile switching center/visitor location register (MSC/VLR), providing radio coverage over an associated geographic area communicates with the associated HLR. Such communication facilitates the downloading of the necessary subscriber data (also known as subscription data) to the serving MSC/VLR for the provision of mobile service to the traveling mobile station. As a result, regardless of which MSC/VLR is currently serving the traveling mobile station, the mobile station is able to access and utilize its associated subscriber data. Such subscriber data, for example, enable the mobile subscriber to utilize its subscriber features (e.g., call forwarding, call barring) and billing accounts (preferred inter-LATA carrier--long distance carrier).
Each mobile telecommunications network provides multiple subscriber features and services. Accordingly, a mobile subscriber having a subscription with a mobile telecommunications network needs to subscribe to available subscriber features and to provide requisite subscriber feature data thereto. As an illustration, for a call forwarding on busy (CFB) subscriber feature, the subscriber needs to provide a desired forward-to-number to the serving network. Utilizing such subscriber feature data, the serving mobile telecommunications network is then able to provide uniform subscriber features and services to the traveling mobile subscriber.
However, because mobile service providers operate independently of each other, a first mobile service provider may provide a different group of service features than a second mobile service provider. Since a mobile subscriber associated with the second mobile service provider has subscribed to and defined subscription data only with the second service provider, when the mobile subscriber roams into a mobile telecommunications network being served by the first mobile service provider, the mobile subscriber is not able to utilize the additional subscriber features and services provided by the first mobile service provider.
As an illustration, the first mobile service provider provides a high penetration notification (HPN) subscriber feature to its associated mobile subscribers. A mobile subscriber having a subscription agreement with the second mobile service provider, which does not provide the HPN subscriber feature, roams into the first mobile service provider's network. Since an HLR associated with the second mobile service provider and storing subscription data associated with the roaming mobile subscriber retains no subscription data representing the HPN subscriber feature, a serving MSC/VLR within the first mobile service provider's network is unable to provide the HPN functionality to the roaming mobile subscriber. Not being able to utilize additional subscriber features and services being offered by a visited mobile telecommunications network, as illustrated above, is inefficient and undesirable.
Accordingly, there is a need for a mechanism to enable a roaming mobile subscriber to access and to utilize subscriber features being provided by a visited mobile telecommunications network even when such features are not supported by the home mobile telecommunications network.